3:15 to ?:??
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Joined: Jun 2005
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From: NE Ohio
3:15 to ?:??
Looking at doing "A" mod have been looking at a few things, 1 long tube headers, 2 T/C or 3 gears. I figure all three are approx the same money (I could be wrong. but that is my assumption). I am looking to shave about a 1/2 second off my 1/4 mile time. One thing for me is that I don't want to "crack in the motor" i.e. cam, heads or intake manifold. And where I live I still have to have it e-checked so I want to keep the cat's. My car already has 3:15 gears if I go that route what would be my best option with an A4? or do you think I would be better with one of the other mods?
Thanks in advance for any input.
Thanks in advance for any input.
Team Owner
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From: S.W. Ohio. . . . . . NRA Life Member
if you're a dragstrip "frequenter" , then I'd suggest going with -at least- 3.73 rear gears and a higher stall TC. Very possible you'll get more than a .5 improvement 
CHICAGO CREW !
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From: We are living in a Bazzaro World everything is upside down half ass backwards !
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St. Jude Donor '06-'07-'08 & '12
I'm going with 3:90s should be installed in about a week I will let you know then if I made a mistake 
& Vig 2800 stall
& Vig 2800 stall
Instructor
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From: Nashua NH
I would bet Most torque converters would put you close to 1/2 a second. that is a t least a 2800 stall. I went from 3.15's to 3.42's (used Z06 rear) and a vigiliante 3200 stall and it certainly feels a lot quicker. I bet that would be good for at least 1/2 a second if not more. Car is now a blast to drive with the stall. It feels good around town too. Get a cooler with the stall.
Le Mans Master
Joined: Aug 2000
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From: Suffolk, Long Island NY
Installing a yank SY3500 with the stock 3.15 rear took a half second off my times, but the car felt loose. A SS3200 may take a half second off, or close to it, and will still feel nice and tight. But a SS3600 and 3.42/3.73's would feel much quicker.
Le Mans Master
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From: West Michigan crew Mich
CI 7-8-9 Veteran
St. Jude Donor '07-'08 & '12
I went from 2.73 to 3.73 and a vig 2800 converter and I have an all new car. Much quicker I have not put it on the track yet but it will really light the tires even from a roll
Melting Slicks
Joined: Jun 2001
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From: Davie Florida
Originally Posted by Face
Installing a yank SY3500 with the stock 3.15 rear took a half second off my times, but the car felt loose. A SS3200 may take a half second off, or close to it, and will still feel nice and tight. But a SS3600 and 3.42/3.73's would feel much quicker.
If you are only going to do one mod go for the SS3200 to go along with your 3.15 gears.
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Joined: Jun 2005
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From: NE Ohio
Thanks for all the input I really do appreciate it, No one seemed to think the LT headers were the way to go? That's interesting as I always thought that was the biggest bang for the buck, but I guess not as big as the T/C? I really don't understand how that could make it faster, but I guess it allows you to launch harder which I know will definately help the ET. Thanks again for all the input, to be honest I was hoping to hear that the Gears or Headers were the way to go, as I am a little worried about cracking in to the motor/trans, but bottom line for me is I want the biggest bang for my buck in the quarter and the idea of a 12 second street car that can be driven all day is something I really WANT!!
Thanks again
Thanks again
Team Owner
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From: S.W. Ohio. . . . . . NRA Life Member
Originally Posted by T1000
Thanks for all the input I really do appreciate it, No one seemed to think the LT headers were the way to go? That's interesting as I always thought that was the biggest bang for the buck,
Rear gears -on the other hand- give a SOTP improvenemt in any gear, at any rpm, (even in overdrive).
Add a high stall TC and you practically have it all.
Team Owner
Joined: May 2005
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From: Flagstaff Az.
mods
I would go with the 3500 or 3600 yank and a used 3:42 diff out of a Z. The labor to install the diff while doing the convertor is minimal($100) and you can pick up a good used diff for $400-500 and sell your 3:15s for the same amount. I had a low milage set of 3:15s I sold for $500.I would not go lower than 3:42 if you do highway driving. The 3:42s and the hi-stall will give you your 1/2 second.
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From: NE Ohio
Thanks again for all the info, are TC and Gears both somewhat close to each other in regards to the labor? In other words would it be crazy to do one without the other because of the labor cost benifet?
Safety Car
Joined: Jul 2001
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From: Ocean Springs MS
Originally Posted by T1000
Thanks again for all the info, are TC and Gears both somewhat close to each other in regards to the labor? In other words would it be crazy to do one without the other because of the labor cost benifet?
Melting Slicks
Joined: Jun 2001
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From: Davie Florida
Originally Posted by fdxpilot
Most off the steps involved are the same, so there is no point in doing it twice. If you're considering a converter at all, get it at the same time as the gears.
Do them both at the same time, don't pay for the same labor twice.
Heel & Toe
Joined: May 2006
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well, you're going to need good tires if you get a stall, especially if you also get gears. I wouldn't go too big with gears since you'll lose top end, because you don't ever want to shift a 4L60E into 4th gear at WOT, so whats 3rd gear @ 6000 rpms with 3.42 gears? 134 according to the gear calculation site. If you get 3.73s your top speed will be only 123, that's no fun at all. Especially when the stock 3.15s will get you up to 145.
I would get a fuddle 3400 stall if you're trying to maintain as much streetability as possible, while getting a great amount of bang for the buck. Fuddle loves to recommend the 3400/2.1 for street/track F-bodies. I dunno why a Corvette would be any different.
I would get a fuddle 3400 stall if you're trying to maintain as much streetability as possible, while getting a great amount of bang for the buck. Fuddle loves to recommend the 3400/2.1 for street/track F-bodies. I dunno why a Corvette would be any different.
Le Mans Master
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From: Suffolk, Long Island NY
Originally Posted by MPe488
well, you're going to need good tires if you get a stall, especially if you also get gears. I wouldn't go too big with gears since you'll lose top end, because you don't ever want to shift a 4L60E into 4th gear at WOT, so whats 3rd gear @ 6000 rpms with 3.42 gears? 134 according to the gear calculation site. If you get 3.73s your top speed will be only 123, that's no fun at all. Especially when the stock 3.15s will get you up to 145.
) up to 150+. What you gain down below will more than make up anything you'll lose up top.